864944455680 has 544 divisors, whose sum is σ = 3129346339200. Its totient is φ = 226605662208.

The previous prime is 864944455633. The next prime is 864944455699. The reversal of 864944455680 is 86554449468.

864944455680 is a `hidden beast` number, since 8 + 64 + 9 + 4 + 4 + 4 + 5 + 568 + 0 = 666.

It is a super-2 number, since 2×864944455680² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 521993412 + ... + 521995068.

Almost surely, 2^864944455680 is an apocalyptic number.

864944455680 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 864944455680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1564673169600).

864944455680 is an abundant number, since it is smaller than the sum of its proper divisors (2264401883520).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

864944455680 is an equidigital number, since it uses as much as digits as its factorization.

864944455680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1762 (or 1726 counting only the distinct ones).

The product of its (nonzero) digits is 132710400, while the sum is 63.

The spelling of 864944455680 in words is "eight hundred sixty-four billion, nine hundred forty-four million, four hundred fifty-five thousand, six hundred eighty".